Wednesday, July 4, 2012

A Universe from Nothing, by Lawrence Krauss


This book was unexpectedly disappointing.  As a non-scientist who reads extensively about cosmology, particle physics, and quantum mechanics, I wasn’t surprised that the author spent the first 142 pages of his book rehashing what we know so far about the formation and evolution of our universe and its component structures.   Some of the information is quite recent, and I expected the foundational knowledge to be important to understanding the argument and evidence that would presumably follow.

Unfortunately, I was fairly well stunned (and disappointed) that he then blithely extrapolated one known phenomenon into a wildly different context with barely an acknowledgement of how different it is, and then declared victory in a ridiculous and unnecessary argument with theists.

It is true that we know from recent experiments that what we long thought of as “empty space” beyond the edges of our solar system is not “nothing.”  Even places in deep outer space that are truly empty of any dust or molecules are still physical structures that are capable of holding matter – similar to how an empty shoe box is still a physical box.

We all know that shoe boxes are made from cardboard, and we now know that space itself is made of a seething sub-microscopic “quantum foam” that contains vast amounts of energy and strangeness.  (See http://www.scaleofuniverse.com/)

Quantum mechanics also tells us that inside this quantum foam, at the tiniest microscopic level, all sorts of particles and anti-particles are constantly winking into and out of existence.   The author describes on page 154 that under the right circumstances, two charged plates can be brought close enough together such that a “real particle-antiparticle pair can “pop” out of the vacuum, with the negative charge heading toward the positive plate and the positive charge toward the negative one.”

As crazy as this sounds, we know from Einstein’s famous equation that energy and mass are essentially interchangeable.   They are different manifestations of the same thing, and under the right circumstances (such as nuclear fusion), we can convert matter into huge amounts of pure energy such as nuclear weapons. 

These same principles suggest it is entirely reasonable for energy to turn into particles (mass), and the author presents a compelling case of how the math works out fine when an equal balance of particles and antiparticles pop into existence, because they represent zero net energy.   (Imagine having two bank accounts with zero balances and then electronically transferring one dollar from one account to the other.  Suddenly one account has one dollar and the other account has a negative balance of one dollar.)

Unfortunately, this is where the author makes a leap of faith that I simply can’t follow.  He concludes that because it is probable (or even certain) that miniscule quantum particles and antiparticles pop in and out of existence inside our spacetime, it must follow that it is possible or probable that the same thing happens outside of spacetime – in a manner that allows for the creation of a quantity of spacetime that is so huge as to be literally mind-boggling.

(Our Milky Way galaxy contains approximately 300 billion stars, and is so vast that it would take a rocket ship (traveling 500 miles per hour) more than 147 billion years just to cross the Milky Way.  And our galaxy is one of more than one hundred billion galaxies in the universe.)

After making the case that it is possible for universes to pop into existence so long as they have zero total energy, the author completely fails to explain why our universe seems to have far more matter than antimatter.  I was expecting him to say there must be vast amounts of antimatter beyond our view , but he instead provided a head-scratching explanation of how the imbalance could have come to be – without addressing the fact that such an imbalance flies in the face of everything he postulated about the primacy of zero energy systems.

Near the end of the book the author unintentionally shows how weak his arguments are when he comes right out and claims that it is a “fact” that “in quantum gravity, universes can and indeed always will spontaneously appear from nothing.”  It may be true that this is so in some version of the speculative (and unquestionably incomplete) theory of quantum gravity.  But it certainly is not a fact and the author’s presentation of it as one is emblematic of the sloppy reasoning found throughout his book.

Finally, a grudging word about the book’s discussion of religion.  I am embarrassed for everyone that a book dedicated to exploring cosmology and scientific principles spends so much time pointing out how the overwhelming huge mountain of scientific facts (based on easily repeatable experiments) conflicts with the mix of inconsistent ancient myths that comprise monotheistic religions. 

From my perspective, "religion versus science" isn't a conversation worth having because religion brings nothing testable to the table.  Religion isn't even the equivalent of a spoon at a knife fight.   (Its more like claiming a cupcake is a great life preserver while living in the desert, far from water.)

I would have greatly preferred that the author split this book into three books.  One being his robust and excellent discussion of modern cosmology, the second being a more logical explanation of his theory of nothingness, and the third being a scientific evisceration of the myths of theistic religions.  Having read the book the author wrote, however, it is clear to me now that he (and/or his publishing company) intended to pick a fight with religion in order to generate buzz, controversy, and sell more books. 

He should have spent more time explaining and defending his central theory, and laying out the case for the next generation of scientific experiments that we should perform in order to prove or disprove his theory.

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